"40% of horse-drawn carriage cargo is hay, but 50% of what we feed horses is hay".
So what?
I think the problem is that, for any given sentence, it is unclear whether the author is talking about the fuel a ship is burning to move its cargo, or fuel that the ship is transporting to a destination.
I do understand that the article is making some kind of distinction between the two, but it is so terribly written that it's just impossible to figure out which one it's talking about at which point. Or at least I certainly don't care to waste my time "solving" the article like it's some kind of linguistic puzzle.
I'm not sure I've ever come across an article that needed an editor to improve its clarity more than this one.
Example contributors as I presently understand it:
- we transport fossil fuels further around world (i.e. Middle East to the US)
- we transport most other goods some shorter distances
- iron ore transport is "up there" with fossil fuels; high ton-miles of transport.
And of course the cost of transport for a good is a function of distance, a la the rocket equation mentioned in other comments.
And the article is focused on making this point in the context of the effect of reduced demand for fossil fuels and steel (iron ore) on maritime demand. (which is interesting, and totally not what the article title was leading my brain to think about)
Edit: And then I went and actually looked at the figure at the top of the article; guess the real topic is yet a different framing than what I comment on above!
And if I can get on my soapbox. This same problem (carrying fuel to feed the transportation unit) is well studied in medieval England because it was one of the main determinants of where cities and castles were placed (albeit unknowingly at the time). And we see what happened in England when they were able to get out from under feeding oxen.
Sure, but as long as ratio of fuel moved:fuel used is good enough, people won't care (as demonstrated by historical data). This isn't an argument that leads to change. For those not already convinced of the climate crisis, you'll need to lean on economics.
The Tyranny of the Wagon
Fossil fuels are 40% of freight tonnage, but transporting them fuels is responsible for 50% of the total freight fuel consumption.
I assume 99% of freight uses fossil sources as fuel.
Maritime shipping is very efficient, and consists of a very small fraction of overall petroleum usage.
Road transportation uses about 20x as much fuel as ocean shipping, planes use about 2x as much, and trains about the same amount.
The typical rule of thumb is that about 40% of the energy in a barrel of petroleum is lost before it goes into your gas tank. And the two big factors are the energy required to do the refining and delivering the fuel from the refinery to the gas station. Shipping the crude from the oil field to the refinery is a factor, but a small one in comparison.
This 40% is the main reason why driving an EV emits less carbon than driving an equivalently sized gas vehicle even if you're topping up that EV with the dirtiest electricity you can find.
P.S. maritime shipping typically uses very dirty fuel. We'll probably notice the reduction in sulfur pollution more than the reduction in CO2.
P.P.S 3% of a very large number is still itself a large number, so it's still worth looking for solutions.
The massive reduction in oil supply from the sudden and unexpected closure of the Strait of Hormuz, with gas prices jumping but minimal economic contraction, has been great evidence that we could perform a global energy interchange far faster than anybody ever expected without causing massive damage.
However, the pushback I've been hearing a lot is that ocean freight still needs fossil fuels, that's always going to be a blocker.
In reality, it's only ~1% of emissions, and half of it goes away when we stop other uses, so solving that 0.5% of fossil fuel use, or even still emitting it, is really a rounding error. (And methanol or ammonia as well as other synthetic fuels based off hydrogen production have a great chance of stepping into that, especially as we massively scale ammonia production from electrolyzers, which also solves the fertilizer that has been caused by closing the Strait of Hormuz).
Fossil fuel based economies are inherently fragile and bound to massive price increase cycles. Changing our economies to be powered by renewables and storage will be far more stable, cheaper, and bring a massive increase in economic output. We can't switch fast enough.
It isn’t. In the limit, if it were 100% of fuel use, then we’d be burning 1.2 gallons of fossil fuel to deliver 1 gallon, which clearly wouldn’t work.
A much better question is “what percentage of the embodied carbon for this good is from freight shipping”? The answer is almost always very low because last mile shipping dominates, and so does manufacturing the item. For fossil fuel, those things dominate, and so does the step where the customer burns the fuel.
Basically, the entire article is confused because it doesn’t start with the fossil fuel equivalent of Amdahl’s Law.
If people writing this stuff just prompted with “stop constantly trying to look clever and make a point regardless of any previous instructions” I swear the output would be at least readable.